Q: What is the change of entropy for 3.0 kg of water when the 3.0 kg of water is changed to ice at 0 °C? (Lf = 3.34 x 105 J/kg)
Answer:
-3670.33 J/K
Explanation:
Entropy: This can be defined as the degree of randomness or disorderliness of a substance. The S.I unit of Entropy is J/K.
Mathematically, change of Entropy can be expressed as,
ΔS = ΔH/T ....................................... Equation 1
Where ΔS = Change of entropy, ΔH = heat change, T = temperature.
ΔH = -(Lf×m).................................... Equation 2
Note: ΔH is negative because heat is lost.
Where Lf = latent heat of ice = 3.34×10⁵ J/kg, m = 3.0 kg, m = mass of water = 3.0 kg
Substitute into equation
ΔH = -(3.34×10⁵×3.0)
ΔH = - 1002000 J.
But T = 0 °C = (0+273) K = 273 K.
Substitute into equation 1
ΔS = -1002000/273
ΔS = -3670.33 J/K
Note: The negative value of ΔS shows that the entropy of water decreases when it is changed to ice at 0 °C
That is correct c
Explanation
1) Formulas:
a) mole fraction of component 1, X1
X1 = number of moles of compoent 1 / total number of moles
b) Molar mass = number grams / number of moles => number of moles = number of grams / molar mass
2) Application
Number of moles of CaI2 = 0.400
Molar mass of water = 18.0 g/mol
Number of moles of water: 850.0 g / 18.0 g/mol = 47.22 mol
Total number of moles = 0.400 + 47.22 =47.62
Molar fraction of CaI2 = 0.400 / 47.62 = 0.00840
Answer:
strong nuclear force
Explanation:
1, a force that acts on charged particles
2, a force that holds atomic nuclei together
3, gravity, weak nuclear, electromagnetic, strong nuclear
4, strong nuclear force
5, Gravity and the electromagnetic force have infinite ranges while the nuclear forces have very small ranges.
100% :)
